Educational Fiscal Policy and Its Effects on How our Children Learn: Comparing Minnesota and Illinois

The study compares Illinois’ and Minnesota’s education fiscal policies. Illinois funds it’s education system mainly from the local level, whereas Minnesota funds it’s mainly from the state level. Thus, in Illinois, if there are discrepancies between household incomes in wealthier and poorer areas, the schools in wealthier areas would receive more money than those in poorer areas. Test scores are then compared. Illinois typically has lower scores than Minnesota. The conclusion is that Illinois’ policies are hindering their students’ learning, compared to Minnesota students, with some mixed results

Stabilization mechanism of molecular orbital crystals in IrTe2

Doped IrTe2 is considered a platform for topological superconductivity and therefore receives currently a lot of interest. In addition, the superconductivity in these materials exists in close vicinity to electronic order and the formation of molecular orbital crystals, which we explore here by means of high-pressure single crystal x-ray diffraction in combination with density functional theory. Our crystallographic refinements provide detailed information about the structural evolution as a function of applied pressure up to 42 GPa. Using this structural information for density functional theory calculations, we show that the local multicenter bonding in IrTe2 is driven by changes in the Ir-Te-Ir bond angle. When the electronic order sets in, this bond angle decreases drastically, leading to a stabilization of a multicenter molecular orbital bond. This unusual local mechanism of bond formation in an itinerant material provides a natural explanation for the different electronic orders in IrTe2. It further illustrates the strong coupling of the electrons with the lattice and is most likely relevant for the superconductivity in this material

Crop Production 4-1976.

Boron carbide is a ceramic material with unique properties widely used in numerous, including armor, applications. Its mechanical properties, mechanism of compression, and limits of stability are of both scientific and practical value. Here, we report the behavior of the stoichiometric boron carbide B$_{13}$C$_2$ studied on single crystals up to 68 GPa. As revealed by synchrotron X-ray diffraction, B$_{13}$C$_2$ maintains its crystal structure and does not undergo phase transitions. Accurate measurements of the unit cell and B$_{12}$ icosahedra volumes as a function of pressure led to conclusion that they reduce similarly upon compression that is typical for covalently bonded solids. A comparison of the compressional behavior of B$_{13}$C$_2$ with that of α–B, γ–B, and B$_4$C showed that it is determined by the types of bonding involved in the course of compression. Neither ‘molecular-like’ nor ‘inversed molecular-like’ solid behavior upon compression was detected that closes a long-standing scientific dispute

High-Pressure and High-Temperature Chemistry of Phosphorus and Nitrogen: Synthesis and Characterization of α- and γ-P3N5

The direct chemical reactivity between phosphorus and nitrogen was induced under high-pressure and high-temperature conditions (9.1 GPa and 2000-2500 K), generated by a laser-heated diamond anvil cell and studied by synchrotron X-ray diffraction, Raman spectroscopy, and DFT calculations. alpha-P3N5 and gamma-P3N5 were identified as reaction products. The structural parameters and vibrational frequencies of gamma-P3N5 were characterized as a function of pressure during room-temperature compression and decompression to ambient conditions, determining the equation of state of the material up to 32.6 GPa and providing insight about the lattice dynamics of the unit cell during compression, which essentially proceeds through the rotation of the PN5 square pyramids and the distortion of the PN4 tetrahedra. Although the identification of alpha-P3N5 demonstrates for the first time the direct synthesis of this compound from the elements, its detection in the outer regions of the laser-heated area suggests alpha-P3N5 as an intermediate step in the progressive nitridation of phosphorus toward the formation of gamma-P3N5 with increasing coordination number of P by N from 4 to 5. No evidence of a higher-pressure phase transition was observed, excluding the existence of predicted structures containing octahedrally hexacoordinated P atoms in the investigated pressure range

Stability of Fe,Al-bearing bridgmanite in the lower mantle and synthesis of pure Fe-bridgmanite

The physical and chemical properties of Earth’s mantle, as well as its dynamics and evolution, heavily depend on the phase composition of the region. On the basis of experiments in laser-heated diamond anvil cells, we demonstrate that Fe,Al-bearing bridgmanite (magnesium silicate perovskite) is stable to pressures over 120 GPa and temperatures above 3000 K. Ferric iron stabilizes Fe-rich bridgmanite such that we were able to synthesize pure iron bridgmanite at pressures between ~45 and 110 GPa. The compressibility of ferric iron–bearing bridgmanite is significantly different from any known bridgmanite, which has direct implications for the interpretation of seismic tomography data

Pressure-induced high-spin/low-spin disproportionated state in the Mott insulator FeBO3

The pressure-induced Mott insulator-to-metal transitions are often accompanied by a collapse of magnetic interactions associated with delocalization of 3d electrons and high-spin to low-spin (HS-LS) state transition. Here, we address a long-standing controversy regarding the high-pressure behavior of an archetypal Mott insulator FeBO3 and show the insufficiency of a standard theoretical approach assuming a conventional HS-LS transition for the description of the electronic properties of the Mott insulators at high pressures. Using high-resolution x-ray diffraction measurements supplemented by Mössbauer spectroscopy up to pressures ~ 150 GPa, we document an unusual electronic state characterized by a “mixed” HS/LS state with a stable abundance ratio realized in the R3 ¯ c crystal structure with a single Fe site within a wide pressure range of ~ 50–106 GPa. Our results imply an unconventional cooperative (and probably dynamical) nature of the ordering of the HS/LS Fe sites randomly distributed over the lattice, resulting in frustration of magnetic moments. © 2022, The Author(s).EAR-1634415; U.S. Department of Energy, USDOE: DE-FG02-94ER14466; Office of Science, SC: DE-AC02-06CH11357; Argonne National Laboratory, ANL; University of Chicago; Israel Science Foundation, ISF: 1189/14, 1552/18, 1748/20; Helmholtz Association; 122021000039-4The authors would like to thank Dr. A. Chumakov (ESRF, Grenoble, France, Kurchatov Institute, Moscow, Russia) and Dr. G. Smirnov (Kurchatov Institute, Moscow, Russia) who provided us by high-quality single crystals of FeBO, Prof. L. Dubrovinsky and Prof. D. I. Khomskii for valuable discussions, Dr. V. Prakapenka and Dr. I Kantor for experimental assistance with the facilities of the 13ID-D GSECARS beamline of APS and Dr. S. Clark for experimental assistance with the facilities of the beam line 12.2.2 at ALS, Berkeley. We are grateful also to the team of the ID-27 beamline of the European Synchrotron Radiation Facility, Grenoble, for assisting with the powder XRD measurements. A few Mössbauer spectrum at 115 and 140 GPa were collected at the ID-18 beamline of the European Synchrotron Radiation Facility. We are grateful to Dr. D. G. Merkel, Dr. R. Rüffer and Dr. A. Chumakov for their assistance in using beamline ID-18 and Dr. G. Hearne and Dr. E. Carleschi for assisting with the SMS measurements. This research was supported by Israeli Science Foundation (Grants No. 1189/14, No. 1552/18 and No. 1748/20). I.L. acknowledges support by the state assignment of Minobrnauki of Russia (theme “Electron” No. 122021000039-4). Portions of this work were performed at GeoSoilEnviroCARS (The University of Chicago, Sector 13), Advanced Photon Source (APS), Argonne National Laboratory. GeoSoilEnviroCARS is supported by the National Science Foundation–Earth Sciences (EAR-1634415) and Department of Energy– GeoSciences (DE-FG02-94ER14466). This research also used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Parts of this research were carried out at P02.2 station of PETRA-III, DESY. 3The authors would like to thank Dr. A. Chumakov (ESRF, Grenoble, France, Kurchatov Institute, Moscow, Russia) and Dr. G. Smirnov (Kurchatov Institute, Moscow, Russia) who provided us by high-quality single crystals of FeBO3 , Prof. L. Dubrovinsky and Prof. D. I. Khomskii for valuable discussions, Dr. V. Prakapenka and Dr. I Kantor for experimental assistance with the facilities of the 13ID-D GSECARS beamline of APS and Dr. S. Clark for experimental assistance with the facilities of the beam line 12.2.2 at ALS, Berkeley. We are grateful also to the team of the ID-27 beamline of the European Synchrotron Radiation Facility, Grenoble, for assisting with the powder XRD measurements. A few Mössbauer spectrum at 115 and 140 GPa were collected at the ID-18 beamline of the European Synchrotron Radiation Facility. We are grateful to Dr. D. G. Merkel, Dr. R. Rüffer and Dr. A. Chumakov for their assistance in using beamline ID-18 and Dr. G. Hearne and Dr. E. Carleschi for assisting with the SMS measurements. This research was supported by Israeli Science Foundation (Grants No. 1189/14, No. 1552/18 and No. 1748/20). I.L. acknowledges support by the state assignment of Minobrnauki of Russia (theme “Electron” No. 122021000039-4). Portions of this work were performed at GeoSoilEnviroCARS (The University of Chicago, Sector 13), Advanced Photon Source (APS), Argonne National Laboratory. GeoSoilEnviroCARS is supported by the National Science Foundation–Earth Sciences (EAR-1634415) and Department of Energy– GeoSciences (DE-FG02-94ER14466). This research also used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Parts of this research were carried out at P02.2 station of PETRA-III, DESY